Hospital consultants are threatening to take industrial action in an unprecedented move over pay.

The president of the Irish Medical Organisation (IMO), Dr Peadar Gilligan, said the union is calling on the Government to immediately engage in talks to end the unfair treatment of senior hospital doctors employed since 2012.

The IMO said it was conducting a national survey among consultants to ascertain the level of industrial action which may be taken in the event the Government did not engage constructively.

"Consultants working beside each other and doing the same job with the same level of responsibility and qualifications are being paid significantly poorer rates of pay for the same work," he said.

"The pay difference will rise to €50,000 in the coming months following an agreement to finally pay the correct salary to consultants recruited before 2012. The HSE is struggling to fill consultant posts and this will continue to be the case.

"There are now almost 500 unfilled consultant posts, which is directly impacting on patient care as manifested by the growing waiting lists for hospital care (more than 700,000 now on waiting lists)."

Dr Gilligan welcomed an acknowledgement in the report by the Public Service Pay Commission which said the reductions in pay which were applied to consultants appointed since 2012 were "particularly severe", and the differential in pay between the pre-existing cadre of consultants and these new entrants is greater than for other categories of public servants.

The pay commission went on to recommend the parties to the Public Service Stability Agreement jointly consider what measures could be taken to address this difficulty.

The IMO "on behalf of doctors employed in the health services, demand Government immediately engage", Dr Gilligan said. The pay commission highlighted that the lack of applicants for consultant posts is indicative of an ongoing problem in regard to the recruitment of consultants.

"Consultant posts are failing in many cases to attract a single applicant - this would have been unheard of even a decade ago when there was fierce competition for every post."

Dr Gilligan said doctors in general had not traditionally tended to engage in industrial action to resolve matters.

"However, the frustration and anger at this issue, which has been long-running, makes that prospect more likely.

Meanwhile, nurses have found an unexpected ally in Tánaiste Simon Coveney who has acknowledged the difficult and stressful conditions they have been working under across Irish hospitals.

The Irish Nurses and Midwives Organisation (INMO) staged protests in Cork and Limerick yesterday - and vowed that rolling protests would continue over what the union slated as chronic under-recruitment of nursing staff at Irish hospitals.

The INMO warned that the Health Service Executive (HSE) had failed to properly act over record overcrowding last summer across Irish hospitals - with some hospitals now entirely dependent on the 11th-hour recruitment of nursing staff from countries outside the EU such as India.

However, Mr Coveney said he understood their concerns.

"I have family members who work in the health system and have done in Ireland for a number of years now," he said. "It can be very difficult - there are some parts of the health system that are working really well. Others are putting staff under real stress."